This invention relates to providing a system for improved monitoring of a vehicle electrical system. More specifically, this invention relates to the continuous monitoring of voltage charge within the electrical system of a motor vehicle having an electrical generation source and a secondary, typically electrochemical, cell or battery.
The lead-acid storage battery has proven to be an efficient and reliable electrochemical energy source since its commercial introduction about 125 years ago. In addition to being a highly efficient energy source, lead-acid storage batteries are also relatively inexpensive to produce and therefore lend themselves to a broad range of applications.
Motorized vehicles are one common example of a commercial use for lead-acid storage batteries. Typically, electrical systems found within motorized vehicles comprise an alternator, secondary storage battery, circuit controlling devices (such as an ignition switch) and a variety of current-drawing electrical loads. During normal operation, the battery is used to start the vehicle's engine, thereinafter the engine drives an alternator that charges the secondary storage battery while the engine is operating. To charge the battery, the alternator must produce an output voltage higher than that of the open-circuit voltage of the battery. This “elevated” voltage condition causes current to flow into the battery, thereby charging it. It is well known that the performances of motor-driven alternators vary greatly. This is especially true of compact alternator units employed in, for example, production of motorcycles. Depending on the output of the alternator, the combined loads of the various electrical devices, and the condition of the battery, the voltage within the electrical system may fluctuate between conditions of severe voltage overcharge and severe voltage undercharge. Both overcharge and undercharge conditions are potentially damaging to electrical system components, to the point of rendering the host vehicle inoperable. Often, the motor vehicle operator is unaware of a pending failure until the vehicle fails to start on attempting to start the engine.
Existing systems to meter the voltage status of vehicular electrical systems have been either inexpensive and acutely inaccurate or relatively accurate but exceedingly expensive and complex to implement. Often an indication of impending failure is marked by very small fluctuations in electrical system voltage. These small fluctuations in voltage are presently undetectable by inexpensive charge warning indicators. Therefore, a need exists within the motor vehicle industry for an inexpensive but highly accurate predictive device to monitor the voltage condition of a vehicular electrical system.